Re: [PATCH 1/2] sctp: implement memory accounting on tx path

From: Greg KH
Date: Wed May 06 2020 - 02:47:30 EST


On Wed, May 06, 2020 at 07:50:53PM +0530, ashwin-h wrote:
> From: Xin Long <lucien.xin@xxxxxxxxx>
>
> commit 1033990ac5b2ab6cee93734cb6d301aa3a35bcaa upstream.
>
> Now when sending packets, sk_mem_charge() and sk_mem_uncharge() have been
> used to set sk_forward_alloc. We just need to call sk_wmem_schedule() to
> check if the allocated should be raised, and call sk_mem_reclaim() to
> check if the allocated should be reduced when it's under memory pressure.
>
> If sk_wmem_schedule() returns false, which means no memory is allowed to
> allocate, it will block and wait for memory to become available.
>
> Note different from tcp, sctp wait_for_buf happens before allocating any
> skb, so memory accounting check is done with the whole msg_len before it
> too.
>
> Reported-by: Matteo Croce <mcroce@xxxxxxxxxx>
> Tested-by: Matteo Croce <mcroce@xxxxxxxxxx>
> Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx>
> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>
> Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
> Signed-off-by: Ashwin H <ashwinh@xxxxxxxxxx>
> ---
> net/sctp/socket.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)

<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree. Please read:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>